List of all critical errors
Below is a comprehensive list of critical error categories across IT, software, hardware, networking, cloud, databases, operating systems, security, DevOps, and enterprise systems. These are the types of failures that can stop applications, cause data loss, impact security, or significantly affect users.
| Category | Critical Errors |
|---|---|
| Software | Application Crash, Fatal Error, Runtime Exception, Stack Overflow, Out of Memory, Memory Leak, Null Pointer Exception, Segmentation Fault, Buffer Overflow, Deadlock, Race Condition, Infinite Loop, Invalid State, Dependency Failure, Library Missing, Version Conflict |
| Operating System | Kernel Panic, Blue Screen of Death (BSOD), System Hang, Boot Failure, Driver Failure, Service Failure, Registry Corruption, File System Corruption, Permission Failure |
| Hardware | CPU Failure, RAM Failure, Disk Failure, SSD Wear-out, Hard Drive Bad Sectors, Motherboard Failure, GPU Failure, PSU Failure, Overheating, Fan Failure, CMOS Battery Failure, Peripheral Failure |
| Storage | Disk Full, Read Failure, Write Failure, RAID Failure, File Corruption, Partition Loss, Volume Failure, I/O Error, Backup Failure |
| Networking | DNS Failure, Connection Timeout, Packet Loss, Gateway Timeout, Network Unreachable, Host Unreachable, Connection Refused, SSL Handshake Failure, Certificate Expired, Proxy Failure, Firewall Blocked, VPN Failure, DHCP Failure, IP Conflict |
| Internet/HTTP | HTTP 400, 401, 403, 404, 405, 408, 409, 410, 413, 414, 415, 422, 429, 500, 501, 502, 503, 504, 505, 507 |
| Database | Connection Failure, Query Timeout, Deadlock, Constraint Violation, Transaction Rollback, Data Corruption, Replication Failure, Lock Timeout, Index Corruption, Database Full, Authentication Failure |
| Authentication | Invalid Credentials, Token Expired, Session Expired, Multi-Factor Authentication Failure, Account Locked, Authorization Failure, OAuth Failure, SAML Failure |
| Security | Unauthorized Access, Malware Detection, Ransomware Attack, SQL Injection, Cross Site Scripting (XSS), Cross Site Request Forgery (CSRF), Privilege Escalation, Certificate Validation Failure, Encryption Failure, Data Breach |
| Cloud | Instance Failure, Auto Scaling Failure, Storage Bucket Unavailable, IAM Permission Denied, API Rate Limit Exceeded, Region Outage, Service Unavailable, Load Balancer Failure |
| Virtualization | VM Boot Failure, Hypervisor Failure, Snapshot Failure, Resource Exhaustion, VM Migration Failure |
| Container/Docker | Container Crash, Image Pull Failure, Container Restart Loop, Network Failure, Volume Mount Failure |
| Kubernetes | Pod CrashLoopBackOff, ImagePullBackOff, Node Not Ready, OOMKilled, Scheduling Failure, Deployment Failure, Persistent Volume Failure |
| DevOps/CI-CD | Build Failure, Test Failure, Deployment Failure, Pipeline Failure, Artifact Missing, Rollback Failure, Configuration Drift |
| API | Invalid Request, Authentication Failure, Authorization Failure, Rate Limit Exceeded, Payload Too Large, Unsupported Media Type, Internal Server Error, Service Unavailable |
| Web Server | Apache Failure, Nginx Failure, IIS Failure, Reverse Proxy Failure, SSL Configuration Error, Virtual Host Error |
| Mobile Apps | App Crash, ANR (Android), Low Memory Kill, Background Task Failure, Permission Denied, Push Notification Failure, In-App Purchase Failure |
| Desktop Applications | Missing DLL, Runtime Error, COM Failure, Application Freeze, Dependency Missing |
| Email Systems | SMTP Failure, IMAP Failure, POP3 Failure, Mail Queue Failure, Authentication Failure, DNS MX Failure |
| Power & Environment | Power Failure, UPS Failure, Cooling Failure, High Temperature, Data Center Outage |
| Backup & Recovery | Backup Failed, Restore Failed, Snapshot Failure, Archive Corruption |
| Logging & Monitoring | Log Overflow, Monitoring Failure, Alert Failure, Metrics Collection Failure |
| Time & Synchronization | NTP Failure, Clock Drift, Timestamp Mismatch |
| Filesystem | Permission Denied, File Locked, File Not Found, Path Too Long, Read Only Filesystem, Corrupted Filesystem |
| Messaging Systems | Queue Overflow, Message Loss, Consumer Failure, Producer Failure, Broker Failure |
| Cache Systems | Cache Miss Storm, Cache Corruption, Cache Eviction Failure, Redis Failure, Memcached Failure |
| Distributed Systems | Split Brain, Consensus Failure, Leader Election Failure, Replication Lag, Network Partition |
| Microservices | Service Discovery Failure, Circuit Breaker Open, Dependency Failure, Service Timeout, API Contract Mismatch |
| IoT & Embedded | Firmware Corruption, Sensor Failure, Communication Failure, Device Offline |
| AI/ML Systems | Model Loading Failure, Inference Failure, GPU Memory Exhausted, Feature Mismatch, Model Drift |
| Browser | JavaScript Runtime Error, CORS Error, CSP Violation, Cookie Blocked, Local Storage Full |
| Payment Systems | Transaction Failed, Payment Gateway Timeout, Duplicate Transaction, Fraud Detection Triggered |
| License & Activation | License Expired, Activation Failed, Invalid License Key |
| Printer & Devices | Paper Jam, Offline Printer, Driver Missing, Spooler Failure |
| Human Errors | Wrong Configuration, Accidental Deletion, Incorrect Deployment, Wrong Credentials, Misconfigured Firewall, Wrong DNS Configuration |
Most Common Critical Errors
Software
- Fatal Error
- Application Crash
- Out of Memory
- Memory Leak
- Null Pointer Exception
- Stack Overflow
- Segmentation Fault
- Deadlock
- Race Condition
Hardware
- Disk Failure
- RAM Failure
- CPU Failure
- PSU Failure
- Overheating
- Motherboard Failure
Networking
- DNS Failure
- Connection Timeout
- SSL Certificate Error
- Gateway Timeout
- Packet Loss
- Firewall Blocked
Database
- Connection Failure
- Query Timeout
- Deadlock
- Data Corruption
- Transaction Rollback
Cloud
- Service Unavailable
- IAM Permission Denied
- Region Outage
- Storage Failure
- Auto Scaling Failure
Security
- Unauthorized Access
- SQL Injection
- XSS
- Ransomware
- Data Breach
- Privilege Escalation
DevOps
- Build Failure
- Deployment Failure
- Pipeline Failure
- Rollback Failure
Approximate Number of Error Types by Domain
| Domain | Approx. Error Types |
|---|---|
| Software | 40–60 |
| Hardware | 30–50 |
| Operating Systems | 30–40 |
| Networking | 80–120 |
| HTTP Status Codes | 60+ |
| Database | 50–80 |
| Security | 100+ |
| Cloud | 80+ |
| Kubernetes & Containers | 50+ |
| DevOps | 40+ |
| Filesystems | 30+ |
| Authentication & Authorization | 30+ |
| Messaging Systems | 20+ |
| Browser/Web | 40+ |
| AI/ML | 20+ |
Overall: Across modern IT ecosystems, there are well over 1,000 distinct named error types, error codes, and failure conditions when considering operating systems, programming languages, databases, cloud providers, networking protocols, hardware vendors, HTTP standards, and enterprise platforms.
For building an IT Error Codes website or SaaS, you can realistically catalog 5,000–20,000 unique errors by including vendor-specific codes (Windows, Linux, AWS, Azure, SQL Server, MySQL, Oracle, Cisco, VMware, Docker, Kubernetes, Android, iOS, Chrome, etc.), making it a substantial and scalable knowledge base.